An intern has gathered details from more than 500 million Facebook members to
create a friendship "map of the world".

Paul Butler, who was an intern with Facebook's data infrastructure engineering team, plotted the friendship networks using current city locations listed on people's profiles.

Applying longitude and latitude coordinates for each city, he then added curved connecting lines between friends to create a unique visualisation of the world. In areas with more friendships he increased the brightness.

Remarkably, the placing of continents and country boundaries is fairly accurate although some areas are noticably missing. China and most of Asia are absent from the map as well as most of central Africa where Facebook has little presence.

The areas with the most friendship connections are primarily within Europe and North America.

In a blog about the social graph, Mr Butler said: "I was a bit taken aback by what I saw. Not only were continents visible, certain international borders were apparent as well.